Multi-stage roll crusher



HF CLPOLLITZ v MULTI-STAGE ROLL CRUSHER March 31, 1959 ZSheets-Sheet 1,

Filed Aug. 24. 1954 1 I I f Harold a Pal/Hz March 31, 1959 v H. c.POLLITZ MULTI-STAGE ROLL CRUSHER 2 Sheets-Sheet 2 Filed Aug. 24. 1954 v,Haro/d 'Pollj/tz United States Ptlttifo MULTI-STAGE ROLL CRUSHER HaroldC. Pollitz, Cedar Rapids, Iowa, assignor to Iowa Manufacturing Companyof Cedar Rapids, Iowa, Cedar Rapids, Iowa, a corporation of IowaApplication August 24, 1954, Serial No. 451,819

9 Claims. (Cl. 241-143) The present invention relates to apparatus forreducing the size of crushable materials and is concerned, moreparticularly, with the provision of a highly compact multistage rollcrusher providing a maximum material reduction with an absolute minimumnumber of rolls.

Rock crushing apparatus of the roll type has been in general use formany decades and has taken many forms. In the past years a great deal ofdevelopment work has been done in connection with improvement of suchapparatus, both from the point of view of simplification of design andin an attempt to obtain greater capacity from apparatus occupying lessspace and requiring fewer operators. While various roll crusherstructures have been proposed for replacing the heretofore commerciallyused plurality of separate different sized crushers, these proposedconstructions have fallen short of commercial; demands inmost cases.

ice

terial size without limitingthe capacity of the machine other than asnecessitated by the first stage crusher pass dimensions.

It is therefore an object of the present invention to provide novelmultiple pass, multi-roll material crusher having a large cmshingcapacity limited by the capacity of the first crushing pass.

Still another object of the present invention is to provide a novelfour-roll crusher providing a first stage crushing pass and threereduced size second stage crushing passes.

Still another object of the present invention is to provide a multi-rollmaterial crusher having an adjustment V for varying the relativepositions of all of said rolls and having an overload release associatedwith each crushing pass to prevent damage to the machine by tramp iron.

Still a further object of the present invention is to pro- "vide amulti-roll, multi-stage crusher having a minimum number of rolls whilehaving a capacity limit determined 'by the capacity of the firstcrushing stage.

A feature of the invention is the provision of four crushing rollspositioned in resilient adjusted association to provide a single firstcrushing stage and three second :stages. 7

Another feature of the invention resides in the provi- :sion ofadjusting means associated with the second stage For example, it hasbeen proposed in the art to manurfacture rock crushers having aplurality of roll passes per machine, on the theory that large chunks ofcrushable material might be fed in the top and that suitably crushed andsized material withdrawn from the machine at the outlet. Heretofore,however, multi-roll or multi-stage: crushing machines have provedunsatisfactory in actual! practice. This is true since it has been foundthat the: limit of the capacity of the machine is determined by the:capacity of the last and smallest crushing passageway=.. The net resultof this is that while it is possible to pro vide a single machinecapable of reducing crushable material from large sizes to a final smallsize, the capacity of the machine is no greater than the capacity ofthe:- small final passageway thereby requiring the machine to operate ata capacity far less than the capacity of theinitial crushing rolls.Under such circumstances it has-- been found much more satisfactory toprovide separate machines as in the earlier systems such that the outputfrom a single coarse crusher is conveyed to a plurality of separate finecrushers.

The present invention will, however, operate to crush. material througha plurality of stages with a minimum of crushing rolls while at the sametime the capacity of the crushing machine is limited solely by thecapacity of the initial crushing passage, within ordinary commercialcrushing size ranges. provision of a pair of first stage crushing rollsoperating. with a pair of secondary rolls cooperatively engaged with.the first stage rolls to provide three second stage crushing: passages.Thus, although the crushing passages in the second stage aresubstantially smaller than the initial stage crushing passage, in orderto provide a further reduction. in material size, nevertheless byproviding the plurality of a multi-stage crusher whereby material flowthrough the second stage may be controlled to provide a maximum crushingefficiency without at the same time permitting a backing up of materialin the first stage of the crushing machine.

Still a further object of the present invention is to provide a crushingmachine having a primary crushing stage and a plurality of secondarystages the latter of which may be adjusted to different widths wherebyblending for the correct gradation of material may be accomplished.

Still other and further objects and features of the present inventionwill at once become apparent to those skilled in the art from aconsideration of the attached :sheets of drawings wherein a preferredembodiment of the present invention is shown by way of illustrationonly, and

of'second stage passes or passageways for each individual.

first stage passageway the second stage passageways are-g capable ofhandling all of the material leaving the first. stage.

mitting a substantial range of crusher adjustment for ma-- 'Wherein:

Figure 1 is a side elevational view. of a crushing appaatatusconstructed according tothe present invention;

Figure 2 is a side elevational view of a crushing apparatus constructedin accordance with the present invention and illustrates the oppositeside of the machine from that shown in Figure 1; and

Figure 3 is a diagrammatic elevational view of the crushing rollersutilized in the present invention and illus trating the action thereof.

As shown on the drawings:

As may be seen from a consideration of Figures 1 and 2, the crushingapparatus of the present invention comprises generally a frame member 10supporting four rotatable crushing rolls 11, 12, 13 and 14 ofsubsantially the same transverse length. As may be seen, the roll 11 ismounted in a fixed bearing 15 supported in the bearing support 16 whichis in turn rigidly secured to the frame 10. For purposes ofsimplification, the frame comprises a pair of substantially identicalside frame members 10 having horizontal top rail 10a, vertical end rails10b and horizontal bottom rail 100. The two frames 10 may be secured toeach other through any suitable means, such as for example the crossbeams shown in dotted lines at 17 in Figure 1. A suitable base isprovided'for the frame by means of brackets 18 welded to the horizontalbottom frame member 10c.

By rigidly securing the bearing supports 16 to the frame members 10, theaxle 19 of the roll 11 is prevented from movement other than rotationthusproviding a .fixed drive axis for the remaining rolls. As may beseen, the axle 19 is fitted with a gear 20 which cooperates with thedrive pinion 21 rotated by means of the pulley 22 operating under powersupplied through belt 23.

In order to eliminate complete rigidity in the system, the remainingrolls 12, 13 and 14 are each mounted for both adjustment and resiliency.Thus, the roll 12 is supported by means of its axle 24 in bearing blocks25 adjustably positioned by means of set screws 26 and resilientlymaintained in the adjusted position by means of the coil springs 27.Since the bearing support 16 carries the member 25 in slidableconnection therewith, the resiliency provided by the spring 27 permitsthe axle 24 to move horizontally toward and away from the axle 19 of thefirst roll 11, under overload conditions which will be described below.Likewise, the adjustment 26 permits the gap 23 between the rolls 11 and12 to be adjusted for the desired degree of crushing.

Immediately below the rolls 11 and 12, the rolls 13 and 14 arecounter-rotatively mounted on respective axles 29 and 30. The axles 29and 30 are rotatably mounted in the pivotally mounted bearing supports31 and 32 carried respectively by the pivots 33 and 34. As viewed inFigure l, the supports 31 and 32 are urged in clockwise andcounterclockwise direction respectively by means of the springs 35 and36 having adjustable tension controls 37 and 33. Movement resulting fromthe action of the springs 35 and 36 is limited by means of theadjustable stops 39 and 40 which determine the operating clearance orgaps 41 and 42 between the pairs of rolls 11, 13 and 12, 14. justed bymeans of the stops 39 and 40 and a resilient overload release isprovided by means of the springs 35 and 36 in the same manner as theoverload release is provided for the roll 12 by means of the spring 27.

A lateral adjustment in the horizontal direction is provided between therolls 13 and 14 by means of adjustments 43 and 44 for the support posts45 and 46 carrying the pivots 33 and 34, respectively. By providingthreaded nuts 47 and 48 fixedly secured to the bottom rails ltlc of theframe, the support posts 45 and 46 may be caused to slide along thebottom rail to provide the adjustability above described. It will benoted that in view of the relatively large diameter of the rolls 11, 12,13 and 14, a single adjustment may be provided in one of the posts 45 or46 if desired wtihout causing a substantial variation in the gaps 41 and42 during adjustment in the transverse or horizontal direction. Such anarrangement would, of course, decrease slightly the cost of theapparatus and may under certain circumstances therefore be desirable.that adjustment of the rolls 13 and 14 along the horizontal plane beaccomplished equally thereby maintaining the gaps 41 and 42substantially identical.

In "iew of the resiliency of the roll supports, finger gears or the likehaving a substantial amount of play are utilized for transmitting thedrive from the main gear 20 to the individual rolls. The drive isaccomplished through these finger gears to the respective rolls by meansof finger gears positioned as may be seen from a comparison of Figures 1and 2 showing opposite sides of the crusher apparatus. As may be seen,the gear 20 which is positioned on the front of the machine as shown inFigure l is driven from the main drive gear 21 and causes the roll 11 torotate by means of the driving connection between the axle 19 and thegear 20. On the eel: side of the machine a finger gear 50 is providedfor making engagement with the finger gear 51 on the roll .12 and withthe finger gear 52 fixedly secured to the axle 529 of the gear roll 13.'From the above interconnection, it will be apparent that power isdirectly applied to the rolls 12 and 13 from the main driving roll 11.

Power is applied to the secondary roll 14 'by means of the gear 53secured at the opposite end to the axle 29 from gear 52, as shown inFigure 1. As is there illustrated, the gear 53 is indrivingconnectionwith gear 54 on the Thus, the gaps 41 and 42 mayreadily be ad- However, it is preferred 1 axle 30 of the roll 14. Sinceall of the gears 50, 51, 52, 53 and 54 are ofthe same diameter andnumber of teeth, the speed of rotation of all of the rolls 11, 12, 13and 14 will be identical. It will be understood, however, that in somecases it may be desired that the speed of the rolls 13 and 14 bedifferent from the speed of the rolls 11 and 12 and that in such casesin view of the direct drive between the rolls 13 and 14 through thegears 53 and 54 such a speed change could be effected through amodification ofthe number of teeth on the gears 50 and 51. In operation,material to be crushed is placed in the hopper 55 and from thence passesbetween the crushing rolls 11 and 12, as shown in Figure 3. The materialpassing between the rolls 11 and 12 is crushed to a maximum dimensionequal to the width of the passage 28 between the rolls and is dischargedinto the space 56 immediately therebelow. A second reduction in materialsize is then effected by means of the second stage rolls 13 and 14operating in cooperation with the first stage rolls 11 and 12 and alsosimultaneously in cooperation with each other. As shown in. Figure 3,the coarsely crushed material collected in the interim space 56 mayproceed in any one of three directions. In view of the counterrotation,or opposed rotation, of the rolls 13 and 14, which is provided byclockwise rotation of the roll 13 and counterclockwise rotation of theroll 14 as viewed in Figure 3, there is a tendency for the rolls 13 and14 to force the material collectedin the space 56 outwardly to the rightand to the left through the passages 41 and 42, crushing the materialbetween the rolls 11, 13 and 12, 14, respectively. However, a gap 57 isprovided between the rolls 13 and 14 and is, preferably, of the samedimension as the passages 41 and 42. As a result, material having adimension smaller than the dimension of the gap 57 will drop downwardly,through the passage 57 onto a discharge conveyor. Material having adimension greater than that which will pass through the secondary gap orscreening passageway 57 will be alternatively carried through one or theother of the secondary crushing passages 41 and 42 in which the materialwill be crushed to the same size as that passing through the passage 57.In this manner, three separate discharge paths are provided for handlingthe crushed material from the single first stage crushing passage 28.

In actual operation,.as an example, it has been found that a first orprimary stage of crushing wherein a passage dimension of approximately2-2/2 inches is provided at 28, is very satisfactory. Under suchcircumstances it is preferred that the second stage passages 41, 42 and57 have a dimension of approximately /8-% inch. Using a crushingapparatus with a roll diameter of thirty inches stone or similarcrushable material having an externalv diameter of approximately 44%inches may be crushed to /s% inch in a single pass through the crushingapparatus, a total ratio of reduction of approximately six to one, at acrushing rate dictated solely by the amount of stone or similar materialcapable of acceptance by the first stage rolls 11 and 12. This willremain the case as long as the combined area of the three second stagepassages 41, 43 and 57, does, not fall below the area of the firstpassage 28.

It has been found desirable during the crushing opera-- tion to adjustthe positions of the respective rolls so that the crushed output fromthe second, stage passages 41, 42 and 57 is at a rate just below thatrate at which the material beginsto. back up in the space 56. Byproviding such adjustment, to diminish the dimensions of the passages41, 42 and 57, a crushing pressure is applied to themassof materialinthe space 56 causing the material to be forced under a positive, thoughslight, pressure through the crushing passages 41 and 42. It will beunderstood that while conventional rolls have been herein described asthe crushing apparatus, nevertheless the presentinvention includeswithin its scope other rotating types of crusher apparatus such as forexample, the impact type wherein the rotating members carry projectingimpact implements for reducing the dimensions of the material.

being crushed.

As was pointed out above, each of the passages 28, 41 and 42, at whichcrushing pressure is applied to the, material, is provided with anoverload relief in the form of a yielding spring controlling theposition of the roll axis. Thus, the passage 28 may be enlargedmomentarily upon an overload by forcing the axle 24 toward the leftagainst the spring 27 as viewed in Figure 1 and, likewise, the passages41 and 42 may be momentarily enlarged upon compression of the springs 35and 36, respectively. This provision for yielding upon overload isprimarily for purposes of permitting tramp iron or other miscellaneousuncrushable materials to pass through the crushing passageway withoutdamage to the crushing apparatus. The springs 27, 35 and 36 are,however, sufficiently strong to prevent opening of the passages 28, .41and, 42, respectively, except to pass such items as stray pieces ofmetal or the like and effectively prevent the passage of large sizeuncrushed, although crushable, chunks of material. It will be apparent,of course, that the passage 57 need not be yielding in nature since theaction of the rolls 13 and 14 is such as to urge the material beingcrushed upwardly into the crushing passages 41 and 42 and away from thepassage 57. Thus, only particles that will fall freely through thepassage 57 against the counter action of the rolls themselves, will passtherethrough. Thus tramp iron of a size larger than the passage 57 willbe carried by the roll 13 or the roll 14 upwardly into the yieldingpassage 41 or 42, respectively.

From the above, it will be apparent that I have provided a novel andunusually efficient crushing apparatus of the multi-stage type which iscapable of reducing stone or similar crushable material at a rate far inex cess of that obtainable by multi-stage crushers of the prior art. Byproviding a novel interrelationship between the first and second stagerollers, a plurality of second stage crushing paths are provided foreach first stage path thereby permitting the passage of the materialthrough the second stage of crushing at a rate at least as great as therate of discharge of the first stage. As a result, contrary to theoperation of crushing apparatus known in the prior art, the apparatus ofthe present invention is limited in its output solely by the maximumcrushing rate of the first stage. By thus eliminating the majorbottleneck heretofore experienced in the crushing field, the amount ofmachinery necessary to reduce stone or similar material fromquarry andpit size to finished size is greatly reduced and the supplementalsecondary or second stage crushing apparatus previously necessary inorder to operate the first stage crushing apparatus at full speed hasbeen completely eliminated. Further, the conveyors necessary inconnection with such supplemental second stage crushing apparatus hasbeen eliminated with the result that the only conveyor equipment nowrequired is a conveyor for loading the hopper 55 and a second conveyorfor collecting and discharging the crushed material from the threeoutlet second stage crushing passages 41, 42 and 57.

Additionally, as will be readily apparent from the drawings and theabove description, the secondary passages 41, 42 and 57 are susceptibleof independent adjustment. Accordingly, it is possible to blend thefinal crushed product for correct size gradation. Thus, for example,where it is desired that a final product be no greater than one inch insize with more than half of the product Vs inch or smaller and the restof a size between and one inch, the secondary passageways 41 and 42could be adjusted to and 1 inch respectively or vice versa. Thus thematerial passing through passageway 41 would be less than Vs inch whilethat passing through passageway 42 would be less than one inch indiameter.

It will be appreciated, of course, that screening passage-1 way 57 mayalso be adjusted as an additional means for providing a blend ofmaterial sizes, thereby providing a crushing machine having threediiferent secondary pas sageways and practically an infinite variety ofblends of final material sizes.

It will be appreciated that various modifications and variations may bemade to the above described structure without departing from theconcepts of the present invention. For example, it will be noted thatvarious types of adjustments may be substituted for the adjustmentsrather diagrammatically shown in the drawings. Further, it will beunderstood that side plates may be provided between the ends of therolls 11, 12,13 and 14 and the frame 10 to confine the stoneor othermaterial being crushed. Such side plates have been omitted in thedrawings in order to'more clearly illustrate the relationships betweenthe component parts. In view of the variations possible withoutdeparting from the novel concepts herein disclosed, it is my intentionthat the scope of the present invention be limited solely by theappended claims.

I claim as my invention:

1. A multiple roll crushing machine comprising a pair of primarycrushing rolls positioned for simultaneous counterrotation adjacent butseparated from each other and having axes lying in a substantiallyhorizontal plane, means for rotating said rolls to draw material to becrushed downwardly through the primary crushing passage therebetween,and a pair of secondary rolls positioned immediately below said primaryrolls for rotation counter thereto, each of said secondary rolls havingits surface positioned adjacent the bottom surface of one of the primaryrolls but separated therefrom to provide a secondary crushing passagebetween each secondary roll and its respective primary roll, saidsecondary rolls being positioned adjacent each other and adjustablyspaced apart to provide a third secondary passage therebetweensubstantially directly below said primary passage, each of saidsecondary passages having substantially the same dimension and beingindividually of lesser dimension than said primary passage butcollectivelyof larger dimension.

2. A multi-roll crushing machnie comprising two primary rolls and twosecondary rolls, said primary rolls being positioned adjacent butseparated from each other for rotation in opposite directions abouthorizontal axes to provide a primary crushing passage through whichmaterial is drawn downwardly by said primary rolls, said secondary rollsbeing positioned adjacent but separated from each other and each beingimmediately below a respective primary roll, each of said secondaryrolls being driven to rotate in opposition to the primary roll thereabove whereby a laterally directed secondary crushing passage isprovided between each secondary roll and the primary roll thereabove,said secondary rolls being adjustably spaced apart for simultaneouslyproviding a secondary screening passage therebetween for passing crushedmaterial of a dimension the same or less than the dimension of saidsecondary crushing passages whereby three secondary passages areprovided for handling the flow of crushed material from said singleprimary passage.

3:. A multi-roll apparatus for crushing frangible material comprising, apair of spaced primary rolls mounted on parallel horizontal axes androtatable in opposition to provide a force tending to draw materialplaced on i the top surface of said rolls downwardly into the spacetherebetween for primary crushing, means for adjusting the width of thespace between said primary rolls, a pair of secondary rolls each ofwhich is positioned below one of said primary rolls in spaced relationto the surface thereof and on an axis parallel thereto to provide a pairof secondary passages for moving material from. the; exitof: saidprimary rolls: laterally for secon'dary crushing, and.meansfor.adjusting the' distance between said secondary rolls to provide anadjustable secondary sieve passageway below the: space between saidprimary rolls.

4. A multi-roll apparatus for crushing frangible material comprising, apair of spaced primary rolls mounted on parallel horizontal axes androtatable in opposition to provide a force tending to draw materialplaced on the top surface of'said rolls downwardly into the spacetherebetween for primary crushing, means for adjusting the width of thespace between said primary rolls, a pair of secondary rolls each ofwhich is positionedbelowone of' said primary rolls in spaced relation tothe surface thereofand on an axisparallel thereto to provide apair ofsecondary passages for moving material from the exit of said primaryrolls laterally for secondary crushing, means for adjusting the widthof'each of said secondary passageways, and means for adjusting thedistance between said secondary rolls to provide an-adjustable secondarysieve passageway below said space between said primary rolls.

5. A multi-roll apparatus for crushing frangible material comprising, apair of spaced primary rolls mounted onparallel horizontal axes androtatable in opposition to provide a force tending to draw materialplaced on the top surface of said rolls downwardly into the spacetherebetween for primary crushing, means for adjusting the width of thespace between said primaryrolls, a pair of secondary rolls each of whichis positioned below one of said primary'rolls in spaced relation to thesurface thereof and on an axis parallel thereto to provide a pair ofsecondary passages for moving material from the exit of said primaryrolls laterally for secondary crushing, means for adjusting the width ofeach of said secondary crushing passages, means for adjusting thedistance between said secondary rolls to provide an adjustable secondaryscreening passageway below said space between said primary rolls, andmeans yieldably supporting the axes of at least one of said primaryrolls and of said secondary rolls whereby non-frangible materials may bepassed through the space between said primary roll and said secondarypassages. without injury to said apparatus.

6. A' multi-roll apparatus for crushing frangible material comprising, apair of spaced primary rolls mounted on parallel horizontal axes androtatable in opposition to provide a force tending to draw materialplaced on the top surface of said rolls downwardly into the spacetherebetween. for primary crushing, means for adjusting the width of thespace between said primary rolls, a pair of secondary rolls eachof whichis positioned below one. of said primary rolls in spaced relation to thesurface thereof: andonaniaxis parallel thereto to provide a pair ofsecondary passages for moving material from the exit of said. primaryrolls laterally for secondary crushing, and positive drive meansconnecting one of said-primary rolls 1 to the-other of said primaryrolls to assure simultaneous opposed rotation thereof and connectingsaid one primary roll to one of said secondary rolls for providingsimultaneous rotation thereof with said one primary roll, and meanspositively drivingly connecting said last named secondary roll to theother of said secondary rolls for simultaneous counterrotationtherewith.

7. Thestructureset forth in claim 6 wherein said driving means comprisesin each case a pair of finger gears.

8. A multi-roll apparatus for crushing frangible material comprising apair of spacedprimary rolls having a crushing passagetherebetween of afirst large width, and apair of secondary rolls each of which ispositioned below one of' said primary rolls and spaced therefrom toprovide a secondary crushing passage of a smaller dimension than saidprimary crushing passage whereby crushed material from said primarypassage may be crushed in said secondary passages without limiting thecapacity'of said primary passage, and means for adjusting the widths ofsaid secondary passages independently of each other to form saidsecondary passages with dimensions differing from each other to providea blended crushed product.

9. A multi-roll apparatus for crushing frangible material comprising apairof spaced primary rolls having a. crushing passage therebetween of afirst large width, and a pair of secondary rollsv each of which ispositioned below one of said primary rolls and spaced therefrom toprovide a secondary crushing passage of a smaller dimension than saidprimary crushing passage whereby crushed material fromsaid primarypassage may be crushed in said secondary passages without limiting thecapacity of said primary passage, said pair of secondary rolls beingspaced to provide a secondary screening passage, and means foradjusting-said secondary passages independently of each other to providea blended product.

References Cited in the file of this patent UNITED STATES PATENTS566,992 Manes' Sept. 1, 1896 1,044,832 Wall Nov. 19, 1912 FOREIGNPATENTS 8,424 Great. Britain Apr. 7, 1906 18,256'v Australia: Aug. 5,1929 78,696 Switzerland Aug. 16, 1918 271,780 Great Britain June 2, 1927317,132 Italy Apr. 25, 1934

